package com.text0309;

public class Bird {
    public int age = 10;
    public void move(){
        System.out.println("飞翔");
    }

    public static void main(String[] args) {
        //Penguin penguin = new Penguin();
        //penguin.move();
        Bird bird=new Penguin();//向上转型
        ((Penguin) bird).show();//向下造型

        Penguin penguin = new Penguin();
        penguin.show();
    }
}
